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Discussion Starter #1
i recently posted about restoring my dads old cb 350 and that the electricals were a mess and it wasent getting spark. i now have spark.. the last time it ran would of been around fifteen years ago and its just been sitting in a shed since then, and im just working on getting one cilinder going and then the other one, when you kick it it occasionally coafs and splutters, and i was wondereing if anyone could give me tips on getting it running. or if anyone else has got one going that has been in the same situtaion..
cheers
 

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ok i would say we all have here done what you are doing. i got a pile that i am working on. well for first offs i would yank carbs and clean. I mean really clean like with one of those $19 dip kits @autozone or spray real good and blow it out real good. you may want to do a compression test. if the compression is low you might want to think about motor yank. so you got spark, check compression, clean carbs (gas), and try to fire it up. You may want to change oil quick (dont buy expensive stuff just cheap oil or even rotella for diesel) because once you have it running you are gonna want to change oil again soon but you dont want old oil in there thats been sitting that long), if it runs then yank everything, clean and put back together and have fun riding a classic bike.
 

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Discussion Starter #3
ok thanks, well when i say spark its not a very strong spark, but dad reckons that it always had a weak spark. and is kinda hit and miss but thats with the kick starter what do you recken, is there any easy way to improve the spark with out spending money
 

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If you dont want to spend any cash you might wanna consider going right through your ignition system with WD40 + rag, a shop manual, and a multimetre and clean her up. At least you can be sure your components are not faulty.

My guess is that your plug caps have built up too much resistence over time and by replacing them you will improve spark considerably.

Which part of Oz are ya from? :)
 

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Discussion Starter #5
i live about 25 minutes out of warrnambool which is about 300 kilometers west of melbourne
 

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I have both a CB450 and 500T - the sparks aren't notably very strong on either one. Maybe that's why the specified plug gap is .025 instead of the more common .030, which seems to be the pre-set gap for most plugs. Just for your info: the length of the spark is your secondary voltage and the fatness of the spark is your secondary amperage. My CBs don't have a lot of either - some day I'm going to get a better set of coils. I loved the old British energy transfer systems - if you pulled a cap off a plug on a running motor, you would seriously regret it. And it would start with a stone dead battery in mid winter.
 

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Discussion Starter #7
ok thanks i might have to check the gap in the spark plug then, the electric start has parts missing on it so i tried to tow start it today and got a backfire and then nothing but tonight i put the left carby on the right side cause im just trying to get one cilinder going at a time and it stated to fire instantly, it like starts and then slowly dies just by kicking it, any more tips?
 

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Sensei
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A 350 NEEDS a good battery to run properly...A weak one will fire the bike (kick-starting) but not continue to "run" it as the surface charge is used up.....
You HAVE to do the tune-up/maintenance and check that everything is right......
What's the compression?
Is it timed properly? (coils, caps, plugs and points good?)
Are the valves adjusted correctly?
ETC...Etc......
 

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Discussion Starter #9
yer everything seems good to go, but i think thr problem is its starving for fuel. when i kick it over lots and take the spark plug out its not evan wet, ive pulled the carbys apart and cleaned them and played with the fuel mixture screw. what else should i look at before i give up and restore a sl70 instead which would be easier.
 

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If it seems not to be getting fuel, check for flow with each float bowl off and set the float levels while you're at it. An old starting trick was to tilt the bike way over for a moment (on the tank valve side), rendering the carb floats inoperative and flooding the carbs, then standing it up and cranking it. Worked on the old Brit bikes that didn't have ticklers on the carbs when you tried to start them in cold weather.
 

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Discussion Starter #11
its defently getting fuel into the bowl because it over flows when you kick it a bit.
 

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So you have to set the float levels and check whether the float valves shut off completely. I think you've hit on the reason it won't start - the motor gets flooded with too much fuel.
 

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Discussion Starter #13
well its getting fuel to the fuel bowl but not getting much into the cylinder because the spark is not wet or anything
 

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Clean the carbs properly.... If the float bowls are full and fuel isn't getting to the cylinder, the jets or passages are clogged.... Also, you don't "play" with the mixture screw....Set it to spec and get the bike running, then fine tune.....
 

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Discussion Starter #15
yer ok. also iv seen the word restoring carbys lots on the site, what exactly is involved in restoring a carby
 

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Discussion Starter #16
i had it running tonight for the first time in a long long time, i started it by having a battery charger switched to engine start on the battery and then i put a socket that fittet onto the sprocket spline and hookd up a motorrised drill to that, this got the engine running a lot faster and after a bit of turning over dad sprayed a bit of rp7 into the carby it then fired up and started running by it self, but then there was a shower of sparks coming from near the battery and now only the left cylinder has spark and the right one was the one it was running on. the fuse hasent blown what do yous recken it could be./.
 
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